WASHINGTON - NASA is suffering because it's asked to do too much without adequate support, a new report says.

The Space Foundation report, "Pioneering: Sustaining U.S. Leadership in Space," urges NASA to shed some of its science and research functions and focus again on exploring space.

The foundation notes it's been 40 years since Gene Cernan became the last human to walk on the moon.

"What we've heard virtually since the moon landing is, why can't we do anything that cool anymore," Space Foundation CEO Elliot Pulham said. "Of course, the answer is we can, but it requires focus and it requires organization. What you have (at NASA) is too many rudders. If ... everybody's trying to steer, you're not going to get anywhere very clearly and crisply and cleanly."

To help NASA's transformation and insulate it from constantly shifting political priorities, the foundation recommends that Congress allow the agency to revamp its leadership structure, emphasize long-range planning and create funding flexibility.

Today's report, underwritten by some of the nation's largest aerospace companies, comes amid increasing disenchantment in some circles about the future and scope of the nation's space program.

U.S. astronauts ride Russian rockets to the International Space Station after the shuttle program ended last year. A return to the moon has been scrapped. And a manned trip to Mars is at least 20 years away.

Some of the nation's most revered astronauts, including Cernan, openly question whether NASA, created more than 50 years ago with a single mission and near-limitless resources, has lost its way.

On Wednesday, the National Academy of Sciences is expected to release a congressionally directed examination of NASA's strategic direction and lay out a course of action.

The Space Foundation report released today recommends a number of changes, including:

Direct NASA to focus on "pioneering" missions such as space exploration that the agency is uniquely qualified to carry out. Once that activity is "sufficiently mature," it can be handed off to the private sector.

Appoint NASA's administrator for a minimum five-year renewable term instead of at the president's discretion. The appointment would still require Senate approval.

Require the agency to submit a 10-year-plan "with specific dates, goals, and objectives" and a 30-year plan that provides a broader strategic context. Congress and a specially created commission would evaluate NASA's performance in meeting those goals.

Give NASA more budget flexibility to pay for long-range projects.

The report describes the agency as "an exceptional institution in a tremendous predicament." While praising NASA and its workers for the technical wizardry necessary to land the Curiosity rover on Mars earlier this year, the report laments that U.S. astronauts must rely on foreign countries to hitch a ride to the space station.

"This hardly seems like a space program that is healthy and bound for greatness," the report said.